(1) Field of the Invention
The present invention relates to a volume control for an in-car hearing aid comprising a microphone having an input and an output for receiving and transmitting sound wave signals, a battery-operated earphone and an amplifying circuit connected to the microphone output, the amplifying circuit including a sound level adjustment circuit component.
(2) Description of the Related Art
In the last few years, hearing aids worn on the head of the hard-of-hearing have become smaller and smaller. Progress in the technology of producing hearing aid components has made it possible to reduce the size of the housing of conventional hearing aids worn behind the ear. Nowadays, housing of hearing aids may be built so small that they may be worn even in the ear or the ear canal.
The progressive reduction in the size of the housing of hearing aids has made it necessary to miniaturize the operating elements of the hearing aid, such as switches and sound level adjustments, correspondingly. This has led to adjustment wheels for the adjustment of potentiometers used conventionally for the regulation of the sound level that are so small that they can be manipulated only with considerable difficulty, if at all, by older persons who are hard-of-hearing and whose finger motion ability has often been diminished by age-connected disabilities.